FOR 1061:  Dynamic Storage Functions of Plant Vacuoles During Cold and Osmotic Stress

• Subject Area: Biology
• Term: from 2008 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 61498647

The vacuole represents the largest plant cell organell with several storage functions. In general, plants cannot escape from their location and, therefore, have to adapt to permanently changing environmental conditions. During the onset of cold or osmotic stress, many solutes like, e.g., sugars, sugar alcohols, organic acids, amino acids, potassium and other ions accumulate in the vacuole. This process contributes to the development of cellular stress tolerance. Especially the cell-internal compartimentation of individual molecules is changed and the rate of biosyntheses of suitable solutes must be rapidly adapted.
The underlying transport processes and the biosynthesis, respectively degradation pathways will be in detail analysed. In mutant plants lacking one or several proteins, or in which the activity of one or several proteins are overexpressed, changes in the stress tolerance will be tested. In the special focus are vacuolar sugar- and sugar-alcohol transporter, malate carrier as well as channel proteins. In addition, stress induced changes of the vacuolar energisation by the tonoplast V-ATPase or V-pyrophosphatase will be enlightened. The methods used enclose molecular techniques as well as biochemical and biophysical technologies, recombinant proteins, mass-spectrometric proteome analysis and microscopic techniques. We expect the outcome of our research contributes to the understanding of molecular stress physiology.

• DFG Programme: Research Units

Projects

• Central project (Applicant Neuhaus, Ekkehard )
• Defining the role of the two vacuolar proton-pumps during stress responses (Applicant Schumacher, Karin )
• Dynamics of the vacuolar proteome of Arabidopsis thaliana in response to abiotic stress factors (Applicant Reinders, Jörg )
• Identification of tonoplast membrane proteins involved in cellular response to environmental stress by quantitative/comparative- and phospho-proteomics (Applicant Trentmann, Oliver )
• Impact of vacuolar monosaccharide accumulation on cellular stress response of Arabidopsis. Function of AtTMT type carriers (Applicant Neuhaus, Ekkehard )
• Molecular and physiological characterization of vacuolar disaccharide and polyol transporters and of vacuolar monosaccharide transporter-like proteins (Applicant Sauer, Norbert )
• Molecular mechanism of electrogenic carrier- and pump-mediated vacuolar transport (Applicant Hedrich, Rainer )
• The role of tonoplast protein phosphorylation in activity regulation and protein targeting (Applicant Schulze, Waltraud )
• The role of Vacuolar Hexose Exporters during Stress Response and Development (Applicant Büttner, Michael )

• Spokesperson: Professor Dr. Ekkehard Neuhaus